Yersinia pestis is the pathogen of plague which has caused three pandemics in human history. Understanding the evolution of Y. pestis in different plague foci from the genomic point of view is of deep significance in improving detection, identification, prevention and treatment of plague. The results of the study of genomic evolution of Y.pestis and their practical implications are discussed in this paper. [HS(1*2/3]

Objective Accidental public health emergencies occurred frequently all over the world in the last decade. The problem of how to set up an effective system for prevention and control of infectious diseases has aroused the attention of all the nations worldwide. The present paper discussed the contributions of the clinical laboratory in hospital during public health emergencies by collecting samples, establishing and applying a rapid diagnosis platform for infectious pathogens, ensuring laboratory biosafety, and developing a strategy in case of emergency. These countermeasures may be helpful for the army to establish an effective system and mechanism in handling public health emergencies.

With non-professional based on-site detection mode and miniature , portable and intelligent techniques as the basis , the potential of point-of-care testing ( POCT ) to feedback the result timely and help to make right decisions to handle emergencies has drawn the attention from extensive fields , including clinical investigation , disease control and prevention , quality control , environmental protection , forensic investigation, import and export inspection and so on.In this review, the definition, history and challenge of POCT promotion from qualitative detection to quantitative one were discussed .

Genotype ; Humans ; Yersinia pestis

Objective To detect 10 RNA viruses including Alphavirus in Togoviridae, Flavivirus in Flaviridae, Hantavirus and Nairovirus in Bunyavirudae and SARS-CoV in Coronavirudae by using genechip technique. Methods The universal PCR primers of Alphavirus and Flavivirus and the PCR primers specific for HFRSV in Hantavirus and XJHFV in Nairovirus were designed by DNAStar software. PCR primers specific for SARS-CoV were adopted from WHO website. In addition, all the PCR primers specific for each virus were designed inside the regions of universal primers. These specific primers were utilized for amplification of cDNA probes. The concentration of probes, the hybridization temperature and duration, the formulation of hybridization solution and the washing conditions were optimized. Results The specific hybridization signals could be obtained when the concentration of probes was 0.3?g/?l. Good hybridization signals could be obtained for all the 10 RNA viruses when the hybridization solution contained 20% formamide, and the hybridization reaction was conducted at 60℃ for 1.5 hours. Two or four pathogens could be detected simultaneously when the target nuclear acids were amplified by multiplex PCR. Conclusion The results showed that the virus pathogens could be detected by genechip technique, and the key step was to design suitable primers and probes.

From the data of inspection of the tongue and colonoscopy in 1121 cases it was found that in changes of tongue coating and tongue proper, and colonoscopy were significant differences (P

[Objective]To establish osteoarthritis model in rabbit knees by two kinds of surgery methods,and to explore their applicable conditions.[Method]Seventeen rabbits were divided into three groups(Hulth group,ligament-excised group and control group),they were anesthetized and operated differently according to their group.The rabbits were sacrificed at 1,3 and 6 weeks after surgery.The femoral condylars were harvested and studied in both gross morphological and pathohistological aspect.[Result]The degeneration of articular cartilage of the two surgery groups got worse by time,and their Mankin's scores were significantly higher than those in the control group(P

Objective To study the impact of QseBC on the motility of Salmonella enterica serovar Typhi ( S.Typhi ) . Methods The motility of wild-type ( WT) and null mutants (ΔqseB and ΔqseC) at mid-log phase was investigated by swimming assay.Quantitative RT-PCR was carried out to calculate the transcriptional variation of flhD and qseB among WT,ΔqseB andΔqseC.QseB overexpressing strain was constructed to compare its motility and flhD expression with the wild-type control.Results The result of motility assay showed that the motility of ΔqseB was similar to that of the WT strain , while the motility of ΔqseC was much lower than that of WT .qRT-PCR revealed that compared with WT , the expression of flhD was significantly decreased in ΔqseC while the expression of qseB was increased considerably .The motility of QseB overex-pressing strain was lower .Conclusion The expression of flhD may be regulated by QseBC which has an effect on the motil-ity of S.typhi, and the overexpression of QseB may inhibit the motility .

Objective To establish the rep-PCR DNA fingerprinting technique for typing K. pneumoniae strains and apply it in the epidemiological investigation.Methods The 39 strains of K. pneumoniae were typed by plasmid profile analysis, then their chromosomal DNA were extracted and purified by NaI-lyses-glass-powder absorption method for rep-PCR. Results Different strains of K.pneumoniae showed different rep-PCR fingerprint patterns. Phylogenetic analysis showed that they could be classified into six types, mainly type 1, type 2, and type 3. Otherwise, plasmid profile analysis suggested that there were four types; mainly type 1 which contained only one plasmid.Conclusions (1) Rep-PCR DNA fingerprinting technique developed in this study is enough for epidemiological studies with its high typeability, strong discrimination, simplicity and rapidness. (2) There were three predominant K. pneumoniae transmitted between patients in Taihe Hospital during the last two years, and there might be serious cross-infection among different types.

Small RNAs(sRNAs) play a significant role in the regulation of bacterial growth.When sensing certain environmental cues such as fluctuation of nutrient concentration, temperature, pH, and osmolarity, sRNAs can influence the expression of target genes.The formation of biofilms is initiated by bacteria transitioning from the planktonic to the surface-associated mode of growth, which is a self-produced extracellular matrix composed of proteins, polysaccharides, and DNA.Recent evidences have shown that small RNA plays an important role in the regulation of bacterial biofilm formation.sRNAs have key roles in biofilm formation process by base pairing with target mRNAs or interaction with modulating proteins.This review discussed the regulation mechanism and pathway of sRNAs in bacterial biofilms formation, and summarized three classical regulatory models of sRNAs in bacterial biofilms formation, this review also gives the research status and development direction of sRNAs in bacterial biofilms formation.